Middle-deep layer thickened oil deposit mining method

The invention relates to a middle-deep layer thickened oil deposit mining method which comprises the following steps of arranging an injection-production pattern in a middle-deep layer thickened oil deposit according to well pattern modes of the existing steam huff and puff old well; conducting steam huff and puff for 1-2 years in newly-drilled vertical injection wells or horizontal injection wells, preheating immediate vicinity of wellbores of a newly-drilled injection well, and forming effective communication between the injection well and the pericardial producing well; continuously injecting steam in the vertical injection wells or the horizontal injection wells, beginning to inject normal-temperature ammonium bicarbonate aqueous solution when injected steam achieves designed section plug injection quantity, repeatedly injecting the steam when the continuously-injected ammonium bicarbonate aqueous solution achieves the designed section plug injection quantity, injecting in a reciprocating mode in stagger until comprehensive water content rate of extraction liquid of the producing well of the oil deposit achieves 92v%, then stopping staggered injection, and adopting the producing well to continuously extract oil and discharge liquid in an injection process. By means of the middle-deep layer thickened oil deposit mining method, recovery efficiency of the middle-deep layer thickened oil deposit can be effectively improved.